package edu.uct.tamnd.viettourism.maps;

import java.io.InputStream;
import java.util.ArrayList;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;

import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.protocol.BasicHttpContext;
import org.apache.http.protocol.HttpContext;
import org.w3c.dom.Document;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;

import android.util.Log;

import com.google.android.gms.maps.model.LatLng;

public class Direction {
	public final static String MODE_DRIVING = "driving";
	public final static String MODE_WALKING = "walking";
	
	public Direction() {
	
	}
	public Document getDocument(LatLng start, LatLng end, String mode) {
			String url = "http://maps.googleapis.com/maps/api/directions/xml?"
					+ "origin=" + start.latitude + "," + start.longitude
					+ "&destination=" + end.latitude + "," + end.longitude
					+ "&sensor=false&units=metric&mode=driving";
				try {
					HttpClient httpClient = new DefaultHttpClient();
					HttpContext localContext = new BasicHttpContext();
					HttpPost httpPost = new HttpPost(url);
					HttpResponse response = httpClient.execute(httpPost, localContext);
					InputStream in = response.getEntity().getContent();
					DocumentBuilder builder = DocumentBuilderFactory.newInstance().newDocumentBuilder();
					Document doc = builder.parse(in);
					return doc;
				} catch (Exception e) {
					e.printStackTrace();
				}
				return null;
	}
	public String getDurationText(Document doc) {
		NodeList nl1 = doc.getElementsByTagName("duration");
		Node node1 = nl1.item(0);
		NodeList nl2 = node1.getChildNodes();
		Node node2 = nl2.item(getNodeIndex(nl2, "text"));
		Log.i("DurationText", node2.getTextContent());
		return node2.getTextContent();
	}
	public int getDurationValue(Document doc) {
		NodeList nl1 = doc.getElementsByTagName("duration");
		Node node1 = nl1.item(0);
		NodeList nl2 = node1.getChildNodes();
		Node node2 = nl2.item(getNodeIndex(nl2, "value"));
		Log.i("DurationValue", node2.getTextContent());
		return Integer.parseInt(node2.getTextContent());
	}
	public String getDistanceText(Document doc) {
		NodeList nl1 = doc.getElementsByTagName("distance");
		Node node1 = nl1.item(0);
		NodeList nl2 = node1.getChildNodes();
		Node node2 = nl2.item(getNodeIndex(nl2, "text"));
		Log.i("DistanceText", node2.getTextContent());
		return node2.getTextContent();
	}
	public int getDistanceValue(Document doc) {
		NodeList nl1 = doc.getElementsByTagName("distance");
		Node node1 = nl1.item(0);
		NodeList nl2 = node1.getChildNodes();
		Node node2 = nl2.item(getNodeIndex(nl2, "value"));
		Log.i("DistanceValue", node2.getTextContent());
		return Integer.parseInt(node2.getTextContent());
	}
	public String getStartAddress(Document doc) {
		NodeList nl1 = doc.getElementsByTagName("start_address");
		Node node1 = nl1.item(0);
		Log.i("StartAddress", node1.getTextContent());
		return node1.getTextContent();
	}
	public String getEndAddress(Document doc) {
		NodeList nl1 = doc.getElementsByTagName("end_address");
		Node node1 = nl1.item(0);
		Log.i("StartAddress", node1.getTextContent());
		return node1.getTextContent();
	}
	public String getCopyRights(Document doc) {
		NodeList nl1 = doc.getElementsByTagName("copyrights");
		Node node1 = nl1.item(0);
		Log.i("CopyRights", node1.getTextContent());
		return node1.getTextContent();
	}
	public ArrayList<LatLng> getDirection(Document doc) {
		NodeList nl1, nl2, nl3;
		ArrayList<LatLng> listGeopoints = new ArrayList<LatLng>();
		nl1 = doc.getElementsByTagName("step");
		if (nl1.getLength() > 0) {
			for (int i = 0; i < nl1.getLength(); i++) {
				Node node1 = nl1.item(i);
				nl2 = node1.getChildNodes();
				Node locationNode = nl2.item(getNodeIndex(nl2, "start_location"));
				nl3 = locationNode.getChildNodes();
				Node latNode = nl3.item(getNodeIndex(nl3, "lat"));
				double lat = Double.parseDouble(latNode.getTextContent());
				Node lngNode = nl3.item(getNodeIndex(nl3, "lng"));
				double lng = Double.parseDouble(lngNode.getTextContent());
				listGeopoints.add(new LatLng(lat, lng));
				locationNode = nl2.item(getNodeIndex(nl2, "polyline"));
				nl3 = locationNode.getChildNodes();
				latNode = nl3.item(getNodeIndex(nl3, "points"));
				ArrayList<LatLng> arr = decodePoly(latNode.getTextContent());
					for (int j = 0; j < arr.size(); j++) {
						listGeopoints.add(new LatLng(arr.get(j).latitude, arr.get(j).longitude));
					}
					locationNode = nl2.item(getNodeIndex(nl2, "end_location"));
					nl3 = locationNode.getChildNodes();
					latNode = nl3.item(getNodeIndex(nl3, "lat"));
					lat = Double.parseDouble(latNode.getTextContent());
					lngNode = nl3.item(getNodeIndex(nl3, "lng"));
					lng = Double.parseDouble(lngNode.getTextContent());
					listGeopoints.add(new LatLng(lat, lng));
			}
		}
		return listGeopoints;
	}
	private int getNodeIndex(NodeList nl, String nodename) {
		for (int i = 0; i < nl.getLength(); i++) {
			if (nl.item(i).getNodeName().equals(nodename))
				return i;
		}
		return -1;
	}
	private ArrayList<LatLng> decodePoly(String encoded) {
		ArrayList<LatLng> poly = new ArrayList<LatLng>();
		int index = 0, len = encoded.length();
		int lat = 0, lng = 0;
		while (index < len) {
			int b, shift = 0, result = 0;
			do {
				b = encoded.charAt(index++) - 63;
				result |= (b & 0x1f) << shift;
				shift += 5;
			} while (b >= 0x20);
				int dlat = ((result & 1) != 0 ? ~(result >> 1) : (result >> 1));
				lat += dlat;
				shift = 0;
				result = 0;
				do {
					b = encoded.charAt(index++) - 63;
					result |= (b & 0x1f) << shift;
					shift += 5;
				} while (b >= 0x20);
				int dlng = ((result & 1) != 0 ? ~(result >> 1) : (result >> 1));
				lng += dlng;
				LatLng position = new LatLng((double) lat / 1E5, (double) lng / 1E5);
				poly.add(position);
		}
		return poly;
}
}
